Modern computers to uncover secrets of Duke’s ancient mosses

It’s ironic. The 230,000 specimens of bryophytes -- mosses and their cousins-- in the Duke Herbarium’s massive collection may have evolved some 500 million years ago. But not until 21st-century computer technology will some of their secrets be revealed.

Until now, access to the rich trove of specimens has been limited because they have been catalogued only in paper records. However, a $400,000 grant from the National Science Foundation will enable a team of technicians to scan images of the specimens and code data on them into an online database available around the world.

Duke students can access the database for evolutionary and biological studies in their coursework, and faculty can use the database to find specimens for their research. It’s a rich scientific trove, says biologist Jonathan Shaw, curator of bryophytes.

Our bryophyte and lichen collections are two of the most important and largest in the country," he said. "The bryophytes are probably one of the largest three university-based collections of bryophytes. We have, of course, the best collection of North Carolina mosses in the world, and North Carolina moss diversity is extremely high. A significant percentage of all the species that are present in North America are present in the southeastern United States.

"We also have several hundred ‘type’ specimens, which are those on which new species are based. These are critically important, because they define a species, which really cannot be done from written descriptions or photos," he said.

Modest-looking little plants that nestle in the moist soils of swamps or mountain hollows, mosses fascinate biologists both because of their evolution and their biology, said Shaw.

For one thing, North Carolina is a sort of "Lost World" of plants -- where plants from regions much farther north or south have somehow survived for millennia.

"Here in North Carolina, we have species that are reaching their northern limit from the tropics," he said. "And we have boreal species from the far north that reach their southern limit in the mountains of North Carolina." Shaw recalls that this strange juxtaposition can yield surprises.

"About eight years ago, I was collecting bryophytes in some of the very rich gorges of the Appalachians in southwestern North Carolina. I was just making general collections, and I picked up one moss that didn’t look like any great shakes. But it turned out that it was the first population of this moss found in North America. And the next closest locality for this species was in Guatemala."

Besides giving scientists more ready access to the collection, computerization will also enable Duke bryologists to identify "hot spots" of moss diversity that should be conserved, as well are "dark spots" of regions that are undercollected.

"The mosses are a really biologically important group of plants because they’re very primitive land plants," said Shaw. "So, studies of mosses can help us understand the origins of biodiversity. They’re also starting to become more and more important model organisms for the study of molecular genetics and genomics."

Shaw explained that mosses are especially amenable to genetic tinkering because their adult form contains only one copy of each gene -- a state called haploidy. By contrast higher organisms, from vascular plants to humans, are "diploid," containing two copies of each gene.

"This haploid property of the moss genome has implications both scientific and practical," said Shaw. "In terms of studying evolutionary processes, there is less hidden genetic variation, because there aren’t two copies of each gene. When a mutation arises in a moss species, it is either going to be selected or not by the environment, unless it’s absolutely neutral. This phenomenon allows us to use mosses to understand evolutionary processes in a way that no other group of organisms allows.

"This haploidy also lets us alter or knock out genes and see their effects right away, because there are not second copies to mask the alteration," he said. Using mosses in such studies, said Shaw, will aid in mapping the location of genes of ecological or developmental importance to plants, as well as exploring how multiple genes interact in influencing plant development.

Source: Duke University

Related stories:

Antarctic fossils paint a picture of a much warmer continent
National Science Foundation-funded scientists working in an ice-free region of Antarctica have discovered the last traces of tundra--in the form of fossilized plants and insects--on the interior of the southernmost continent before temperatures began a relentless drop millions of years ago.
The conservation lens
The definition of conservation priorities for biodiversity often focuses only on the numbers of vertebrate animals and seed plants in the northern hemisphere or in the tropics. But what about the other organisms, and the more extreme regions of the world, where the species richness of flowering plants and mammals is low?
Researcher says: No-till practices show extended benefits on wheat and forage
With more than 3 million acres of wheat in north Texas, 50 percent or more of which is grazed by 1 to 2 million head of cattle, it is important to look at tillage practices and their effect on forage production, said a Texas AgriLife Research expert.
Bad sign for global warming: Thawing permafrost holds vast carbon pool
Permafrost blanketing the northern hemisphere contains more than twice the amount of carbon in the atmosphere, making it a potentially mammoth contributor to global climate change depending on how quickly it thaws.
Border Patrol also guards against foreign bugs
(AP) -- Alishia Beckham is on the front lines defending the United States from foreign invaders - armed with weapons that include a hand mirror and a flashlight.
Researchers develop drought-tolerant corn
At the end of the day, drought tolerance in corn has to equate to good yields and good quality, not just good looks, said a Texas AgriLife Research scientist.
Earthquakes may endanger New York more than formerly believed
A study by a group of prominent seismologists suggests that a pattern of subtle but active faults makes the risk of earthquakes to the New York City area substantially greater than formerly believed. Among other things, they say that the controversial Indian Point nuclear power plants, 24 miles north of the city, sit astride the previously unidentified intersection of two active seismic zones. The paper appears in the current issue of the Bulletin of the Seismological Society of America.
Noogoora burr throws researchers a curve ball
(PhysOrg.com) -- What do you do when a weed fights back? Noogoora burr in Australia’s tropical north has done just that but CSIRO scientists aren’t letting it get away with it.

News discussion:

General Science news